Clutch



septz, 1954 w.J. KELLEIGH 2,690,246

CLUTCH l Filed June 29, 1949 "'-ff 14 fz s a e4 y j la of the drivingmember.

by the engagement of the clutch, segmentsthere- Y* of are forced intothe notches'between the serra` Patented Sept. 28, 1954 WaldoJ.'Kelleigh, Wayland,- Mass.;y assignor to `General Control Company,Boston, ll/lass., a corf poration of Massachusetts- Application June-29,19421,;'s/e1y Claims.v (Cl. 192466) In certain types of apparatusemploying me'- chanical clutches it is desirable to avoidinsofar aspossible any inaccuracies of engagement. Devices of this type are, forexample, timers such as represented by the electrical timer described inmy copending application Serial No. `l72,118, led January 22, 1949, nowPatent No. 2,542,085. In this timer a mechanical clutch is used forselectivelycoupling the timing elements with a synchronous motor whichis maintained in continuous operation. Clutches having` positive drivesuch as those with interengaging teeth are preferred for thisservice'because theyv avoid the altogether uncontrollable timingerrorintroduced by any slippage of conventional friction clutches.Although toothed clutches provide a positive drive and limit the errorto the tooth pitch, these clutches are not sufficiently exact for allpurposes since, unless the teeth upon the driving member are in exactalignment with the spaces between lthe teeth upon the driven memberthere is relavrelative position between its driving and driven members,which is simple in operation, which is economical in construction, whichhas a long life, which requires a minimum of maintenance, and whichadvances the art generally.

In a broad aspect the invention contemplates a clutch having driving anddriven members with associated means for moving the members relativelyto each other whereby indentations or serrations upon a surface of oneof the members are brought into contact with a yieldable portion A ofthe other member.' The yieldable portion is made of a material such assynthetic rubber which withstands abrasion,` practically indei-L' nitelyand can be deformed suficientlyto be indented by and to project into theindentations of the first member, while reassuming its normal shape upondisengagement.

In another aspect the driven member carries a ring or torus of yieldablematerial which engages serrations in an inner conically shaped face Asthe torus is deformed 2 aseries of teeth insuring nonslipping betweenthe driving and driven members. As thesegments are formed by theengagement of the'dri'vi'ng members it will be apparent that thereisno-relativeangular movement introduced therebetween. ,l

In still another aspect of the invention the driven member anda xeddriving member are secured to vrespective axially aligned shafts. Amovable" driving member having'a serrated or -otherwise indented surfaceis connected with the `iixedd'riving member so that there is no relative'rotationtherebetween but the movable member 'can be axially translated:by a fork or otherwise with'r'espect tothe fixed driving member to bring'the serrated face into contact with the yieldable torus or l'ringcarried by the drivenv member. 'Such connection vmay be made by one ormore pins arranged parallel tothe axis of the coupled "shafts which'pinsare secured to the fixed mem- ,berl at one end; withtheir other endsslidably 'engaging the movable member; or thevmovable vention referringto drawings in which Fig. 1 is an end elevation view of one embodimentof the invention;

` Fig. 2 is'a side elevation View of the embodi ment shown in Fig. 1; Y

Fig; '3` i's'an end View of the contacting face of the driving membershowing the serrations there- Fig.' 4 is' an exploded view of theembodiment shownI in Fig. `1;

' Fig. 5 is a sectional View on line 5-5 of Fig. 1;

"Fig 6 is an axialsectional view of a second `embodiment of theinvention;

f Fig; '7 is an end view of the contacting face of 'the' drivingmemberof the embodiment shown 'iii'Fig.'6; f

Fig. `8' is an end elevation view of the fork for I `moving the drivingmember into engagement; 50,

and.

" Fig. 9, is a side elevation view of the fork shown "in Fig. c.y

n the embodiment ofthe invention chosen for the purpose of illustrationthe clutch shown in Fig.' 1, comprises a xed driving member such asrespectively. .The .opposite :ends .of-.the pins .slidrhas `a.- series.of .indentationsw .(Fig. 57:.) radially .arranged .forengagingthesynthetic rubber ring.

the sleeve II which is secured to a driving shaft I 2 by means of a setscrew I3. Mounted circumjacent the sleeve II is a bushing I4 (Fig. 5)pressed into a movable driving member I6. The bushing I4 is preferablyof sintered metal impregnated with oil thereby providing practicallypermanent lubrication to reduce friction as the member .lIBis u.anzially.moved the sleeve Ill-as -will be described infde'taillaeneinaiter.

The movable driving member I6 comprises a connecting hub 2| havingformed integrally therewith at its opposite ends an enlarged discportion 22 and a flange 23 respectively. The diameters of the disc 22andaba-manger!) are considerably greater than :diameter cnf hub 2Ithereby defining a circumferential groove 24 for accommodating the.clutch nengaging mechanism described below. `"Relative rotationalmovement between the driving membersalifxand I6 is prevented by atapered pin 26 (Fig. 5) pressed into-.anaperture 2.Ia.in.the.hub-2l .and.extend-ing jthrough.an .aperture .I la of bushing I4, .so :that thecylindrical endzl thereof .engages akeyway-ZB tout axiallyintotheperiphery. ofthe .sleeve Il. This keyway-28 permits.- relative axialmovement between the drivingmembers I.I...and

AII.

.The end.. of `the :disc ..22 -has v.a .tapered .recess 29 the conical.surfacet .of -whichhasa plurality of radially extending .serrationsJ32.. With A.the

clutch .in ltheY.engaged,punsitiori,...thelserratedcon- .ical surface3-I .is contact with. the -outer .,.pe-

riphery of :a unitary body of ,yieldable material which :body has 1 a.continuous .surface .for .direct eng-agementwith indentations such. as.serrations .32. .in thev present embodiment, .this .tbody isa tor-us 33of vyiel-dable materialsuchasa `so-callcd O ring .havingphysical..characteristics .com-- lparable .to those .required forClassB-High Flexibility v.hydraulic .packings :.as -1 required .by

the f-fArmy-Navy. Aeronautical -Specification Packings and Gaskets;Hydraulic, .ANTR-7.9., dated -Augustf-Q, 1.945. .Rings of.-:suchmaterialarevextraordinarily .resistant to wear, extrusiommerma- ;nentset, fatigue, cracking .and disintegration., .Thering 33 :iscarried .ina :groove .34 .between two .-anges .3B l.and ..351 radially projecting.fromml driving members. v.The fixedadrivingmemberrl Ia is secured to adriving shafttawbyfmeansoha -setscrew =I-3a. `-'lwo,.pinsdiproiectfromrthe .face of .the .member 1IIa,..thethreadedends-thereofengaging threads in oppositely disposed apertures ingly engagerespective apertures 42.*.inafmovab1e -driving member. .Ifa whichhas-are'ircumterentially disposed groovec24a.similar.totherfgroove2-411and a tapered recess 25a. The conicalfsurfacefia The ring anddriven member used with.t'hisfem ubodiment :are .similar-.to the.corresponding. `parts .33 .and 38..described. in detailin .connectionwith .the .conical surface. 3,I .(or. 3 la) ...into contact .with

the ring 33..by means .of .aib'i'furcatedmember such asthe llever'llshown' .in`Figs.8.;.and"9 which is similar to the clutch lever 43 in mycopending application Serial No. '7 2,118. Projecting into the groove 24from the respective bifurcated lever ends respectively are two pins suchas the screws 46 whereby clockwise rotation of the lever d4 about asuspending shaft d1 moves the driving member to bring the face 32 intoContact with the ".ring33. The material ofthe ring 33.is:suf`ciently":yieldahle'sc tha-tit deiorms suf'ciently. to enter the indentations 32upon the face in eifect form- .Ling teeth which prevent relativeslippage between the driving and driven members. On the "other hand Ihave found that material of the type :used-'the above identified O ringswithstands zthe :successive deformation and reformation forlaminden-itentime `so as to be capable of continu- .ouslyproviding teethat any given point dened "bythe permanently toothed member, whichtemporaryz=teeth are eliminated upon every engagement to make theresilient member ready for the next .-toothformation. Itwillbe evident.that .the .above described .construction combines-the .ad-

vantages of a smooth face .clutch with those of .a A.130013111clutch,..that is the .engagement of the f :members .does not .introduce`relative angular movement therebetween while v:it .provides thepositive vdrive of a clutch having two Atoothed members.

.Itshould be `understood `thatfthe present disclosure lisfor the purposeof illustration only. and .thatthis .inventionincludes all modificationsand equivalents .whichfall within the .scope of the appended claims.

.,Iclaim:

.'1. A .clutch comprising .a rotatable .driving member .having.aninternal conical .surface with ..a.p`lurality of .serrations whichintersect circles .describedfby ,points on the said conical surface-ofthe .driving member., .a .driven member .carrying a .ur1`itary-lbodyof yieldable material having a torical surfacefor .engaging the saidserrations, .andmeans .for translating the mem-bers relativelytoeachother to bring the .said .toricalsurface into .engagement with.said serrations thereby pre- .venting .relative rotation between saidmembers.

2..A .clutch .comprising a rotatable driving member having an internalconical surface with a plurality of serrations which intersect circles'de- .scri-bedby .points on the said conical .surface of thedr-iving.member.,..a driven member carrying va .unitary .body .of yieldable.material having a {tor-ical-.surface .for selectively engaging the.said serrations, and .a pivotally suspendedv f ork havinga..lo`i'furcated .end for ,axially moving the .driving .member.towards.the driven. member .to bring the said serrations into .engagement withthe said ...torical .surface .thereby preventing relative rota-.betweensa'id members.

.BMA clutch .for transmitting .torque between .twoshafts ycomprising a.fixed vdriving .member .seCuredtoone of. said shafts, a movable:driving .member .having a contacting .surface with fa plu-.ralityo'findentations therein, .adriven member .secured Ito one of.said .shafts .and carrying a unitary Joodyofyieldable material whichbody has .a ,continuous surface .arranged for directly engaging theindentations, a pin attached to one .of said driving members andslidably engaging 'the other 'of said driving ,members and meansfor.translating themoving driving memberrela- 'tively .to. .t'he..fiXeddriving .member .tobring the .indentations-into engagement with .said.surface lthereby. preventing relative .rotation .between .said

'dr'ivingand/dr'iven members.

"l, "A clutch 'for' transmitting torque between two rality ofindentations therein, a radially disposed pin attached to said movabledriven member and slidably engaging the fixed driving member, and meansfor translating the movable driving member relatively to the fixeddriving member to bring the indentations into engagement with theyieldable portion of the driven member thereby preventing relativerotation between said driving and driven members.

5. A clutch for transmitting torque between two shafts comprising a,driven member secured to one of said shafts and having a contactingportion of yieldable material, a xed driving member secured to one ofsaid shafts, a movable driving member having a contacting surface with a20 plurality of indentations therein, two opposed pins axiallyprojecting from the fixed driving member and slidably engaging themovable driving member, and means for translating the movable drivingmember relatively to the xed driving member to bring the indentationsinto engagement with the yeldable portion of the driven member therebypreventing relative rotation between said driving and driven members.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 981,345 Winter Jan. 10, 1911 1,491,267 Joffe et al Apr. 22,1924 1,777,829 Edgecumbe Oct. 7, 1930 2,416,083 Battaline Feb. 18, 19472,481,028 Lear Sept, 6, 1949 FOREIGN PATENTS Number Country Date 237,460Switzerland Aug. 16, 1947 403,745 Great Britain Jan. 4, 1933

